<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
    <div id="app">
        <div id="test">{{msg}}</div>
    </div>
    <script>
        /*  */
        new Vue({
            el:"#app",
            data:{
                msg:"good"
            },
            mounted() {
                this.msg = "hello world"
            },
            beforeUpdate() {
                console.log("beforeUpdate")
            },
            updated() {
                console.log("updated")
            },
            
        })
    </script>
</body>
</html>